Process for breaking petroleum emulsions



atented Juiy 20, 1943 I 2,324, avaaaeia copy PROCESS FOR BREAKING PETROI IEUM EMULSIONS Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., assignors to Petrolite Corporation, Ltd., Wilmington, Del., a

- corporation of Delaware No Drawing. Application July '1, 1941,

Serial No. 401,384

Claims. (Cl. 252-341) This invention relates primarily to the resolution of petroleum emulsions.

;One object of our invention is to provide a novel process for resolving petroleum emulsions of the water-in-oil type, that are commonly referred to as "cut oil, roily oil, emulsified oil, etc.,'and which comprise fine droplets of natural ly-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

Another'object is to provide an economical the polyalkylene glycols employed may be cated by the following formula:

. in which m has its previous significance,

- represents a numeral varying from 2 to 4.

and rapid process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude petroleum and relatively soft waters or weak brines. Controlled emulsification and subsequentdemulsification under the conditions just mentioned is of significant value in removing impurities, particularly inorganic salts, from pipe line oil.

The new chemical compond or composition of matter herein described, that is used as the demulsifying agent of our process, is exemplifiedby the acidic, or preferably, neutral ester derived by complete esterificatlon ofv one mole of a polyalkylene glycol 01' the kind hereinafter described, with two moles of a fractional ester derived from a hydroxylated material of the kind herein described, and a polybasic carboxy acid having not over six carbon atoms,

If a hydroxylated material, indicated for the sake of convenience by the formula T.OH, is

reacted with 'a polybasic carboxy acid, which,

similarly, may conveniently be of the dibasic type and indicated by the formula HOOCDCOOH Thus, the bulk of the materials herein templated, as demulsifiers, may be ind within certain variations, as hereinafter s by the neutral ester derived by esterificat:

one mole of a glycol of the kind above desc with two moles of a fractional ester of the previously described. The formation of the pound may be indicated by the following tion, although obviously, it. is immaterial particular procedure is employed to produ particular chemical compound or product As indicated previously, the polybasic employed are limited to the type havin more than six carbon atoms, for example, I

, and also of the price of the reacants. Gel

then the fractional ester obtained by reaction between equimolar quantities may be indicate by the fol owing formula;

HOOC.D.COO.T The polyethylene glycol may be characterized by materials of the kind such as heptaethylene glycol, octaethylene glycol, nonaethylene glycol, decaethylene glycol, to and including heptadecaethylene glycol. For convenience these polyethyleneglycols may be indicated by the following formula:

OH mH speaking, the higher the temperature cm the easier it is to obtain large yields of t terified product. Although oxalic acid is paratively cheap, it decomposes somewhat ily at slightly above the boiling point of For this reason, it is more desirable to 1 acid which is more resistant to pyrolysis.

larly, when a polybasic acid is available form of an anhydride, such anhydride to produce the ester with greater ease th acid itself. For this reason, maleic anh is particularly adaptable; and also, ever else considered, the cost is comparative. on a per molar basis, even though son higher on a per pound basis. Succini or the anhydride has many 'of the att. qualities of maleic anhydride; and this true of adipic acid. For purposes of l: the bulk of the compounds hereinafter trated will refer to the use of maleic anh although it is understood that any othe able polybasic acid may be employed. F1 more, for purposes'of convenience, refer the use of polyethylenegijycols. As has fractional acidic ester are reacted with one mole :viously indicated, such glycols can here of the polyethylene glycol, there is no possibility v y suitable polypropylene or ruplybut'ylene ior the formation of polymeric types of esteriiiids. v cation products under ordinary conditions. as. the range of oxyalkylated-compounds g .The alcoholic bodies employed are hydroxyd as reactants is concerned,rlt-is our latedacylated diai'nides containing: (a) an acyl cc to employ those having approximately j-f-radical derived from 'a polybasic carboxy acid lalkylene group particularly 8'-12'oxy' *having not more than.6- carbon atoms, andthe groups. Our preference to use the-'oxy-. V acyl radical thereof linked to two amino nl el l' I :1 compounds is due; largely, to the fiact" :atom'si. (b). an acyl radical derived from a deter :y are commerciallyxavailable, and par gent-forming monocarboxy' acid having at least 8 so intwo desirable forms. ,The'most-deand not more than 32 carbon atoms; and (0) an orm is these-called nonethylen'e glycol 1alcoholiiorm hydroxyl radical. I lthough consisting; largelygaof nonaethyl QyDetergent-iormin'g acids'having at least 8 and 01, may contain sinall amounts of'hep lii 'not more than 32 carbon'atoms are exemplified uezand octaethylene glycdls, and posfb'yflfatty acids, naphthenic acids, abietic acids, v, nor "percentages oi? the higher homoi'ogs oxidized paraflin' or wax acids, or the -like.or, by wcoi's 'represent' the upper rangeoi. dis-' siinpiemddifications there0f,',which donut-deef zlycols: and h y ma be conve ie ly I 'tract'from the-ability of the acid to combine with:"' to asfupper distillabie ethylene glycols. alkali to produce soap or soap-like materials. fAs= no particularly godd procedure for makto oxidized petroleum acids,s'ee UJS. Patent No. I arper separatiOnOn-a commercial scale; 2,242,837, dated May 20, 194 1, to Shields. 1' understood that miixtures oione or more -I 'l' ihv hydrogenated oleic acid, chlorinated vcols maybe employed, as Well es a single 'naphthenic acid, or brominated abietic acid will As pointed -out.,itis particularly-me form [such detergent-forming 'bodies with the employ nonaethyleheglycol as c0mn1er-. same-ease as the parent materials themselvesQ 'ailable. although it is understood that "Ifhe oxidized acids obtained by blowing or oxida iuct. contains other h'omOlOgs; as indition of the acids or esters, are satisfactory. Such c E i p acids'ha've frequently been referred to collective- .ntially as desirable! asrthe'upper diso ly in the art as monocarboxy detergent-forming iolyethylene glycols, j are the lower new I acids. Needless to say, the acylation need not be e'polyethylene glycols. These materials conducted by-means of the acid itselt, but-may; able in the formof a'waxy water-soluble I be conducted by-means of any compound of the I ,fan'd the general range'm'ay vary someacid which contains the acid radical; for indecato tetradecaethylene glycol.v "As fiance; an este' gan amide, an anhydi'ide, anacyl, rifderstoodthemethod of producing such. y chloride, etc. H f. 1 n 17 rould cause some, higher homologs to be a It is our preference to use the. fatty acids as and thus; even in this instancefthere'; the most desirable form of'a detergent-forming present some-oxyethyleneglycols within acid; and particularly the unsaturated 'fattyi; er range above indicated. One need not acids; .ior instance, ,r'icinoleic acid, oleieacid. t5 that these particular compounds conmixedfatty acids derived: from soyabean oilg ixtures,and that in someinstances, 'par- 1 w desirable'esters are obtainedh mlet; of the liquid nonaethyleu'e sires-i with xy, lower non-distillable polyethylene iii-like, may he employed.

or the sake of convenience," reference 1: :amples will be to nonaethylene glycol; ulations will be basedona theoretical rweight 01"414. Actually, inmanuiace Iumaric,acid,;ma1ei c. acid, ,aconitic acid, 19 9 2 molecular weight of the glycol em "acid, tartaric acid, citric'lacid. etc. Such acids] 'hethe'r a hizherdis able polyethylene; may be coi'i re niently referred to as low molal'; a' -lower non-distillable polyethylene gly- 2 "polybaslc carbo 'cy cids,' -or, more preferably, low mixture oithe same, should be determolalacids; id reaction conducted on the basis of] regard to'jlioth the'dterg'ent-forininea s armination, particularly in conjui' ction and in regardto the low molai-acids, itisobvious' hydroxyl or acetylvalue. that'one' need 1101711188 the acid. itself 'as"are-; been previously pointed out thatit is actant, but may use some-suitable derivative,- a1 how-the compounds herein contemsuch'as' theacyl chloride, the anhydride'the esre manufactured, although we have tenor amideri nyjs 1 formv yb most desirable to react the selected gly -m used which is a the functional equiv lent in S b re -The polybaslc carbo'iiy acids may be 'ieiil "ployed include oxalic acid, malon'ic acid, succinic acid, glutaricacid, 'adipic acid,- tricarballylic' acid,

xture 'ofslycois-with" maleicanhydiide {p ng the acyl radical. I a of two males of the Eanhydride for one Suitable primary and secondary amines which ;h glycol; Under such circumstances, @maymbc used as primary reactants include the found little tendency. to form longer J- IOHQW M ,l y cl yp ll 'n mi i Ymers; and-infact'the product o'fredcgj'iiionoethanoiamine; ethyl ethanolan ine; i'nethyi: onducted-"at reasonably low temperaa n .e e am ipr 'o no m iear'sto be largely monomeric. For con propyl propanolamine, ctc.-pther'examples1 in suchinter'iriediate fractional estermay 1 vclude cyclohexylolamine, dicyclohexylolamine,,ey onsideredas a dibasic 'r'polybasiciacid clgheityl ethanolainine, cyclohexylpropano1a' -f voigthe intermediate ractionai letter We. bgnzylethanqiaml be y op ol mi a :d, isthen reacted with two molesjojfth peutanolam'ine; ;'hecraiiolamine, ocetylethanola- 1 material of the kind subsequently de octadecylethanolamine, cyclohe'xanolethan'o amine etcifl a I be noted, however, that ii onapreis'rs" If the lowf'inolal-"polycarboxy ac ii'd "happens to v j a1. acidic ester. and ii. two moles or the beehydroxylated, as in the instance of tartaric acid, citric acid, hydroxysuccinic acid, and the like, it is obvious that a hydroxylated detergent-forming acid, for instance, ric-lnoleic acid,

hydroxystearic acid, and the.like, could be esterified therewith, i. 'e., with the hydroxyl glroup' which is part of the low molal acyl radical; and under such circumstances, the primary or secondary amine need not be hydroxylatedl Under these circumstances, one might employ .compounds, such as amylamine, diamylamine, butylamine, dibutylamine, benzylamlne, cyclohexylamine,etc. c.

Other suitable types of amines will be described subsequently. For instance, one may employ the type involving the presence of an ether linkage, as, for example, the following: 1

(321140 C2H4OH "Calm and Harris patent. Said compounds are derived both from low molal monocarboxy acids and low molal polybasiccarboxy acids. It may be well to illustrate both types, in order to understand clearly the manufacture of the intermediate products for use in obtaining the compositions of matter herein contemplated, and particularly when manufactured for use as demulsifiers of water-in-oil emulsions.

Example A, part 1 of the aforementioned Cahn and. Harris patent will serve excellently as an initial illustration and is as follows:

Example A (1') 224 grams of methyl acetate (3 moles) and 210 grams of diethanolamine (2 moles) were mixed together, two layers forming at first, the

mixturebecoming a homogeneous mass after a short time. The mixture was refluxed for 19 tained a compound which was essentially the acetic acid amide of diethanolamine, having the following formula:

OzHrOII Having obtained a material of the kind above described, itds obvious that one can then esterify the material with either one or two moles of a detergent-forming monocarboxy acid, so as to obtain a hydroxylated derivative. Obviously, if

the detergent-forming acid employed does not contain an alcoholic hydroxyl radical, for instance, if it is of the type other than that exemplified by ricinoleic acid, hydroxystearic acid, and. the like, then one can only esterify one mole of such detergent-forming acid with a com-.

pound ofthe kind above described, for the reason that there must be a residual alcoholiform hydroxyl radical. If, however, an acid such as ricinoleic acid, hydroxystearic acid, or the like I is employed, then, of course, two moles of such detergent-forming acid can be employed. Similarly, if desired, one might esterify one hydroxyl with oleic acid, and the other hydroxyl with ricinoleic acid.

If the experiment above described is repeated, using monoethanolamine in the equivalent amount, then the final product is characterized by the following formula:

CgHlOH The limitations in regard to the above type of compound is perfectly obvious. Unless one can produce a secondary amide, which is difiicult, and generally speaking, not-particularly feasible, one must, of necessity, esterify with a hydroxylated detergent-forming acid, such as ricinoleic acid,

V hydroxystearic acid, or the like.

hours at which time 90% of the diethanolamine ha'd reacted. A portion of the reaction mix-' ture was subjected'to a vacuum of 6 millimeters at degrees C. in order to drive off the volatile material, namely, the unreacted methyl acetate and the methyl alcohol which was formed during the reaction. The residue, upon titration, showed-a content of 4.64% of free diethanolamine. grams of methyl acetate were added and the mix- -ture was refluxed for 3 /2 hours. The resulting reaction product was then freed from its low boiling constituents, namely, the methyl alcohol and unreacted methyl acetate, by maintaining the mass at '70 degrees C. under a pressure of 6 millimeters. mately 0.8% of unreacted diethanolamine, based upon a determination of the alkalinity of said residue by titration The product was a light yellow colored syrup, soluble in water, and con To 192.5 grams of this residue, 34.7

If, however, instead of using acetic acid, one uses lactic acid or some'other hydroxylated .low

' molal carboxy acid, then the two formulas above described change to the following forms:

The presence of this additional hydroxyl offers additional Opportunity for reaction, and further elaboration is not necessary, except perhaps, to point out that even a type of material such as the following:

alkyl onomo-rr 0 alkyl might be employed, provided that ricinoleic acid,

The residue contained approxifor example, is e'sterified with the hydroxyl of the low molal monocarboxy acid acyl group. Other variants too numerous to mention suggest themselves, as,'for example, derivatives oftris (hydroxymethyhaminomethane, or similar types of compounds, such as an amide of the following type, which may be used for reaction ,with a detergent-forming acid:

CHzOH exist in view of what has already been said.

can be" employed note which may be utiilzed to produce various type herein contemplated. Such materials as there described are largely derivatives of hydroxylated secondary amines; but for the purposes herein contemplated, such limitation does not In the present instance, however, one is conand it is to be noted that, although many illustrations in the aforementioned Cahn and Harris patent are concerned with low molal monocarboxy acids, the corresponding low molal polybasic carboxy acid compound is readily'obtainable, all

' of which will be obvious, in view of what is said ing procedure set forth in the Cahn and Harris "Q AEain attention is directed to the-aforementioned Cahn a'nd'Harris patent, insofar that it illustrates a large number of intermediate prodamount or a sulfonic acid as a catalyst, for mstance, /a% of toluene sulfonic acid. Inother instances; esterification may be conducted in the presence of an inert solvent, such as xylene, which is permitted to distil oil, carrying water vapor with it. The vapors are condensed, separa- I connection.

I cerned with derivatives obtained from low molol polybasic carboxy acids of the kind described;

patent, and which hasbeen quoted in detail under the item previously identified as Exampl A,

part 1:

- One can employ onepound mole of diethyl oxalate and two pound moles of monoethanolamine and react these compounds in a similar manner;

oxalic acid, along,-wi th the liberation of two poundmoles of ethyl alcohol. 'Suchbis(hy drox-,

l yethyl) oxalicacid diamide may bereacted with ricinoleic acid in the ratio of one pound moleo! thediarnide' for 2 pound moles oi. ricinolelc acidg;

similaaiy,v a product can be obtained employing onlyoue mole of ricinoleic acid for one mole oi the diamide; or one might employ one mole or Y oleic acid and one mole oiricinoleic acidfor each fmo lev of the diamide; T similarly; diethanolamine may. be employed with ,diethyl oxalate to give the g "corresponding ftetramydroxyethyll oxalic acid; dlamide. Instead f-ofdiethyl oxalate,- diethyl maleate or numerous other reactants-canbe em- -ployed Attention is called mor tact that 1 Pld'roxylated polybasiccarboxy'acids might be em-' ployed in thesame' manner as hydroxy acetic acid' the analogous type or comow' molal monoc'arboxy acid is I Byway illustration, thefiollowing examples" will serve:

' 3' rmmE TYPEIIITERMEDIATE FQBQ F of the following composition:

p 'E xampleff I,

One pound moleof a diamideoi the'folloWinB' typeiormula: g

H o n one pound mole of ricinoleic acid in the preced ing example.

HYDROXYLATED DIAMIDE TYPE INTERMEDIATE Example 3 Onepound mole of naphthalenic acid is substituted for ricinoleic acid in Example 1, preceding.

HYDROXYLATED DIAMIDE TYPE INTERMEDIATE Example 4 c I HYnRoxYLA'rEn DIAMIDE TYPE INTERMEDIATE Example 5 One pound mole of oleic acid 'andonepound 'mole of ricinoleic acid are substituted for one pound mole of ricinoleic acid in Example 1, preis' substituted for the amide in v I scribed in the preceding examples, and also having present an appreciable. amountof a diamide' untiliesterification is complete. Such esterificae tionreactio'n can be conducted by'any one oi'the conventional means, usually heating at a temperatu're above the boiling pointof water; 1 nc-' stance,- 116-160 C. is suflicient.- :Insomecases reaction is extended by the presence of a small I -F IYnnoxYLATEo DIAMmE TYPE INTERMEDIATE Example 6 1- The diamide derived from diethanolamine and diethyl oxalate of the following composition:

,OHCzHl O O C2H40H .onclnl CIHiOH Examples 1 -5,

- HYDROXYI-AT-ED DIAMmE TYPE INTER EDIATE Example 7 One pound mole ofi'diethyl oxalate is reacted fwith one pound mole of monoethanolamine and one pound mole of dieth'anolamine to give a mix- .ture containing some diamides of the types de- Suchre'actant is employed in the manner sug- V I gested in Examples 1-5, preceding. is stead with one pound moleor fitment an;

HYDROXYLATED DIAMfiJE TYPE INTERMEDIATE Example 8 employed to givecompounds comparable to those described in Examples 1-7, preceding.

. HYnRoxYLATEn DIAMIDE TYPE INTERMEDIATE I Example 9 One pound mole of diethyl oxalateis reacted Monopropanolamine and dipropanolamine are with tris(hydroxymethyl) aminomethane to give a diamide of the following composition:

Such diamide is substituted in theprevious examples, such as 1-5, inclusive.

'HYDROXYLATED DIAMIDE TYPE INTERMEDIATE Example 10 Diethyl maleate is substituted for diethyl oxalate in Examples 1-9, preceding.

Having obtained hydroxylated acylated amido compounds of the kind previously described, the

' next step, of course, is to obtain fractional esters derived from nonaethylene glycol of the kind described in the earlier part of thepresent disclosure. Such materials may be illustrated by the following:-

GLYCOI. ESTER INT RMEDIATE PRODUCT Example 1 One pound mole of nonaethylene glycol is treated with two pound moles of maleic anl'wdride, so as to formnonaethylene glycol dihydrogen dimaleate.

GLYcoI. ESTER INTERMEDIATE PRODUCT Example 2 A mixture of lower non-distillable polyethylene glycols, representing approximately decato tetradecaethylene glycol, is substituted for nonaethylene glycol in the preceding example.

GLYCOI. ESTER INTERMEDIATE PRODUCT Example 3 A A 5040 mixture of nonaethylene glycol and lower non-distillable polyethylene glycols of the kind described in the previous example is substituted for nonaethylene glycol in Example 1.

GLYCOL EsTER INTERMEDIATE PRODUCT Ezrample 4 Adipic acid is substituted for maleic anhydride in Examples 1-3, preceding. j

GLYcOL EsTER INTERMEDIATE PRODUCT Example 5 Oxalic acidis substituted-for maleic anhydride in Examples 1-3, preceding.

GLYCOL ESTER INTERMEDIATE PRODUCT Example 6 Citric'acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYGOL ESTER INTERMEDIATE PRODUCT Example 7 Succinic anhydride is substituted for maleic anhydride in Examples 1-3, preceding.

. manufacture of ethylene glycol dihydrogen diphthalate. See U. S. Patent No. 2,075,107, date March 30, 1937, to Frasier.

Sometimes esterification is conducted mo; readily in the presence of an inert solvent, th: carries away the water of esterification whic may be formed, although, as is readily apprec ated, such water of esterification is absent whe the-reaction involves an acid anhydride, such maleic anhydride, and a glycol. However, if wa ter is formed, for instance, when citric acid. employed, then a solvent such as xylene may 1 present and employed to carry oif the Wat formed. The mixture of xylene vapors and w: ter vapors can be condensed so that the Water reaction vessel for further circulation. This 'a conventional and well known procedure a! requires no further elaboration.

COMPOSITION OF MATTER Ewample 1 tone pound mole of a glycol ester intermedia product of the kind described under Glycol est intermediate products,'Examples 1, 2 and 3, pr ceding. Such reaction is continued until all c'a boxyl acidity has disappeared. The time of r action may vary from a few hours to as many 20 hours.

COMPOSITION OE MA TER Example 2 The same procedure is followed as in Compo: tion of matter, Example 1, except that one e1 ploys a hydroxylated diamide type intermedia product described in Hydroxylated diamide ty intermediate, Example 2, preceding, instead in Example 1.

COMPOsITION 0F MATTER Emample 3 The same procedure is followed as in Compo: tion of matter, Example 1, except that one e2 ploys a material of the kind described in H droxylated diamide type intermediate, Exam 3, preceding, instead of in Example 1.

. COMPOSITION OF MATTER Example 4 The same procedure is followed as in Compo. tion of matter, Example 1, except that one e1 ploys a material of the kind described in H droxylated diamide type intermediate, Exam 4, preceding, instead of in Example 1.

COMPOSITION OF MATTER Example 5 The same procedure is followed as in Compo tion of matter, Example 1, except that one e1 ploys a material of the kind described in 1-1 droxylated diamide type intermediate, Exam 5, preceding, instead of in Example 1.

COMPOSITION OF MATTER Example 6 The same procedure is followed as in Compo tion of matter, Example 1, except that one e1 ploys a material of the kind described in 1-3 droxylated diamide type intermediate, Exam; 6, preceding,- instead of in Example 1.

COMPOSITION or 'MATTER Example 7 COMPOSITION OF MATTER Example 8 COMPOSITION or MATTER Example 9 be same procedure is followed as in Composiof matter, Example 1, except that one ems a material of the kind described in Hy- :ylated diamide type intermediate, Example 'eceding, instead of Example 1.

COMPOSITION or MATTER Example 10 1e same procedure is followed as in Composiof matter, Example 1, except that one em- 5 a material of the kind described in Hyylated diamide type intermediate, Example. receding, instead of Example 1.

COMPOSITION OF MATTER Example 11 ycol ester intermediate products of the kind tibed by Examples 4-7, preceding, are substil for Glycol ester intermediate products, 1,

d 8, in the preceding ten examples. 40

such previous examples, which include the if ricinoleic acid, attention is directed to the that excellent products of unusual value are .nable by substituting oxyalkylated ricinoleic particularly Oxyethylated ricinoleic acid, in l of ricinoleic acid? -The preparation of such rial is well known, and preferably, involves ollowing procedure:

iricinolein in the form of castor oil is treated 3-12 moles of ethylene oxide for each mole ricinolein. One-half of 1% of sodium stea- :r sodium ricinoleate is used as a catalyst. A erature of 100-200 C. is employed. The ren is conducted varying from 100 lbs. to 300 gauge pressure. The water-insoluble oxyated triricinolein, so obtained, is saponified s to yield a water-insoluble oxyethylated )leic acid, or one, which at the most, is selfsifying. A reviewing what has been said, it is obvious 130 a wide range in carbon atom content exists gard to the alcoholic bodies employed for ion with the glycol dihydrogen diacid ester. may be illustrated by the following exas:

oxalic acid or ethyl oxalate is reacted with ethanolamine, the compound previously de- 1 contains only 6 carbon atoms. If such ml; is then reacted with one mole of octanoic the alcoholic body contains a total of 14 n atoms. On the other hand, a product :d from oxalic acid and diethanolamine has rbon atoms; and if one introduces 4 ricinradicals, one adds 72 more carbon atoms. (1, similar derivatives suggest themselves, 75

whereby three ricinoleyl radicals are introduced, thus adding 54 carbon atoms in each half of the alcoholic radical or each amide group of the diamide. With this in mind, it is obvious-that rather large molecularly sized alcoholic materials can be obtained, if desired. Thus, it is possible that such compounds contain in excess of carbon atoms; indeed, -150 carbon atoms would be present in a number of compounds 10 which readily suggest themselves, in view of what has been said.

It is to be noted that this second step is an esterification reaction, and the same procedure is employed as suggested above in'the preparation of the intermediate product. Needless to say, any particular method may be used to produce the desired compounds of the kind indicated. In some instances it may be desirable to conduct the esterification reaction in the presence of a nonvolatile ,inert solvent which simply acts as a diluent or viscosity reducer.

g In the preceding examples, attention has been directed primarily to the monomeric form, or, at least,.to the form in which the bifunctional alcohol, 1. e., a glycol, and'the polyfunctional acid, usually a bifunctional compound, react to give a chain type compound, in which the adjacentacid and glycol nucleus occur as a structural unit. Forinstance, in the monomeric form this may be indicated in the following manner:

4 acid glycol. acid the tendency would be to produce a product which might be indicated in the following manner:'

acid glycol acid glycol acid Similarly, three moles of the glycol and four moles of the acid might tend to give acombination which may be indicated thus:

yacid. glycol acid glycol acid glycol acid Another way of stating the matter is that the composition may be indicated in the following manner:

or self-emulsifiable compounds; whereas, others. I

give cloudy solutions or solsyand the most desirable type is characterized by giving a' clear solution in water, and usually in the presence of soluble calcium or magnesium salts, and frequently, in the presence of significant amounts of either acids or alkalies.

Water solubility can be enhanced in a number of ways which have been suggested by previous manufacturing directions, for instance:

(a) By using a more highly polymerized ethylene glycol;

(b) By using a polymeric form instead of a monomeric form in regard to the unit which forms the chain between the two alcoholic nuclei;

(0) By using a polybasic carboxy acid of lower molecular weight, for instance, maleic acid instead of adipic acid; and

- butyl alcohol, hexyl alcohol,

a agents.

(d) By using an alcoholic reactant of lower molecular weight, or one having more hydroxyl groups, or possibly, having one or more ether groups.

Indeed, in many instances, the hydroxylated body .may show some tendency towards water solubility, or self-emulsification, prior to reaction with a glycol ester. It is to be noted in this instance that the hydroxylatedmaterials which are'employed prior to reaction with the glycol esterare largely of the water-insoluble type; but in such instances where they are self-emulsifiable; or show hydrophile properties, they are equally suitable.

Actually, a'reaction involving an alcohol and an I acid, (esterification) may permit small amounts of either one or both of the reactants, depending upon the predetermined proportion,

' to remain in an unreacted state. In the actual preparation of compositions of the kind herein contemplated, any residual acidity can be removed by any suitable base, for-instance, ammonia; triethanolamine, or the like, especially in dilute solution. Naturally, precaution should be taken, so that neutralization takes place without saponification or decomposition of the ester. In some cases there is no objection to the presence of acidic group. Indeed, if a tribasic acid be employed in such a manner as to leave one free carboxyl group, then it is usually desirable to neutralize such group by means of a suitable basic material.

In the hereto appended claims, reference to a neutral product refers to one in which free carboxylic radicals are absent.

Conventional demulsifying agents employed in the treatment of. oil field emulsions are used as such, or after dilution with any suitable solvent, such as water; petroleum hydrocarbons, such as gasoline, 'kerosenne, stove oil, a coal tar product,-

such as benzene, toluene, xylene, tar acid oil, cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, octylalcohol, etc., may be employed asdiluents. Miscellaneous solvents; such as pine oil, carbon tetrachloride, sulfur dioxide extract obtained in the refining of petroleum, etc., may be'employed as diluents. Similarly, the material ormaterials herein described may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents, provided that such compounds are compatible. They will be compatible with the hydrophile type of solvent in all instances. Moreovensaid material or materials may be used alone, or in admixture with other suitable well known classes of demulsifying It is well known that conventional demulsify- I ing agents may be used in a water-soluble form,

or in an oil-soluble form, or in a form exhibiting both oil and water solubility. Sometimes they may be used in -a form'which exhibits relatively limited oil solubility. However, since such reagents are sometimes used in a ratio of 1 to 10,000, or 1 to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed. This same fact is true in regard to the material or materials herein described, except that they are invariably water-soluble.

We desire to point out that the superiority of the reagent or demulsifying agent contemplated in our herein described process for breaking p troleum emulsions, is based upon its ability treat certain emulsions more advantageously a1 at a somewhat lower cost than is possible wi other available demulsifier-s, or conventional mi;

' tures thereof. It is believed that the particul ing petroleum emulsions of the water-in-oil typ a treating agent or demulsifying agent of t] kind above described is brought into contact wi1 orcaused to act upon the emulsion to be treate in any of the various ways, or by any of tl various apparatus now generally used to resol or break petroleum emulsions with a chemic reagent, the above procedure being used eith. alone, or in combination with other demulsif: ing procedure, such as the electrical dehydrz tion process.

The demulsifier herein contemplated may 1 employed in connection withiwhat is common known as down-the-hole procedure, i. e., bringir the demulsifier in contact with the fluids of ti well at the bottom of the well, or at some poii prior to their emergence. This particular ty; of application is decidedly feasible when the dl mulsifier is used in connection with acidificz tion of calcareous oil bearing strata, especial I if suspended in or dissolved in the acid employe for acidification.

It will be apparent to those skilled in the a: that residual carboxyl acidity can be eliminate by esterification with a low molal alcohol, f( instance, ethyl, methyl, or propyl alcohol, by cor ventional procedure, so as to give a substantial] neutral product. The introduction of such 10 molal hydrophobe groups does not seriously a1 fect the solubility, and in some instances, give increased resistance, to soluble calcium, an magnesium salts, for such property is of par ticular value. Usually, however, neutralizatio with a dilute solution of ammonia or the lik is just as practicable and less expensive.

Inthe hereto appended claims it is intende that themonomeric forms contemplate also th polymeric forms, insofar that the polymerl forms are nothing more or less than a repetitio:

of the monomeric forms several times over, wit

the loss of one or more moles of water.

Having thus described our invention, what w claim as new and desire to secure by Letter Patent is:

' 1. A process for breaking petroleum emulsion of the water-in-oil type, characterized by sub jecting the emulsion to the action of a demulsify ing agent comprising a water-soluble esterifica tion product, derived by reaction between on mole of a polybasic compound and two moles o a-hyaroxylated acylated diamide; the polybasil compound being the esterification product of (A1 a polyalkylene glycol having at least 7 and no more than 17 ether linkages, and the alkylenl radicalthereof containing at least 2 and no more than 6 carbon atoms; and (B) a polybasi' carboxy acid having not more than 6 carbox atoms; and the ratio of the esterifying reactant being within the range of more than 1 and noof the water-in-oil type, characterized bysubjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-solub1e esterification product, derived by reaction between one mole of a polybasic 'compound'and two moles of a hydroxylated acylated diamide; the polybasic compound being the esterification product of (A) a polyalkylene glycol having'at least '7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying-reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for each mole of. the glycol;.said hydroxylated acylated diamide containing: (a) an acyl radical derivedfrom a polybasic carboxy acid having not more than 6 carbon atoms, and the acyl .radical thereof linked to two amino nitrogen atoms; (is) an acyl radical derived from a detergent-forming monocarboxy acid having at least 8 and not more than 32 carbon atoms; and (c) an alcoholiform hydroxyl radical.

1 and not over 2 'moles of the dibasic acid for each mole of the glycol; said hydroxylatcd acylated cliamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more than -6 carbonatoms, and the acyl radical thereof linked to two amino nitrogen atoms;

(b) an acyl radical derived from a detergentforming monocarhoxy acid having at least 8 and not more than 32 carbon atoms; .and (c) an alcoholiform hydroxyl radical.

r 5. A process for breaking petroleum emulsions of theiwater-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble 'esterification productQderived by reaction between one mole of the dibasic compound and two moles of a hydroxylated acylated diamide; the dibasic compound: being the esteriflcatlon product of (A) a polyethylene glycol having at least 7 and not more than 17 eiuer linkages;

and (B) a .dibasic carboxy acid having not, more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of -more than one, and not over two moles of the dibasic acid for each mole of the glycol; and said hydroxylated acylated amidecontaining:

(a) an acyl radical derived from a 'polybasic *carboxy acid having not more than 6 carbon atoms, and the acyl radical thereof linked to 3. A process for breaking petroleum emulsions of the water-in-oil type, characterized .by subjecting the emulsion to the action of a demul- -sifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a dibasic compound and two moles of a 'hydroxylated acylated diamide; the dibasic compound being the esteriflcation prodnot of (A) a polyalkylene glycol having at least 7 and not more than 1'7 ether linkages, and the lene radical thereof containing 'at least 2 nd not more than 6 carbon atoms; and (B) a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the'es'teriiying reactants being within the range of more than 1 and not over 2 moles of the dibasic acid for each mole of the glycol; said hydroxylated acylated diamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more than 6 carbon atoms, and the acyl radical thereof linked to two aminonitrogen atoms; (b) an acyl radical derived from a detergent-formtwo amino'nitrogen atoms; (12) an acyl radical derived from a detergent-forming monocarbo'xy acid having at least 8 and not more than 32 carbon atoms; and (0) an alcoholiformhydroxyl radical.

6. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demule sifying agent comprising a neutral, water-solu- I ble chemical compound of the following for;-

mula type:

'roooncoot (02mm mC2HiOOC.D.COOl=T I in which '1' is a radical derived by dehydroxyla tion of a'hydroxylated acylated'diamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more than 6 cari bon atoms, and the acyl radical thereof linked ing 'monocarboxy acid having at least 8 and .4

not more than 32 carbon atoms; and (c) an alcoholiform hydroxyl radical.

4. A process for breakingpetroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a dlbasic compound and two moles of a hydro'xylated acylated 'diamide; the dibasic compound being the esteriflcation prodnot of (A) a polyalkylene glycol having at least '7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more-than 4 carbon atoms; and (B) a dibasic carboxy,' acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of morethan to two amino nitrogen atoms; (b) an acyl radical derived from a detergent-forming monocarboxy acid having at least 8 and not more than- 32 -carbon atoms; and (c) an alcoholiform hy-'- droxyl'radical; 0003.000 is the acid radical derived from a dibasic acid by removal of the acidic hydrogen atoms; said acid radical havingnot over 6 carbon atoms; mrcpre'sents'a numeral varying from '7 to 12; and a: is a small:

whole number less than 10.

7. A process for breaking petroleum emulsions of the water-imoil type, characterized by subjecting the emulsion to the action of a demulsil'ying agent comprising a neutral, water-soluble chemical compound of the following formula type;

' TOOC.D ,COO(C2H4O) ntCilHQOOCJlCOO-T in'which T is a radical derived by dehydroxylation of a hydroxylated acylated diamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more than 6 carbon atoms, and the acyl radical thereof linked to two amino nitrogen atoms; (1)) an acyl radical derived from a detergent-forming monocarboxy acid having at least 8 and not more than 32 carbon atoms; and (,c) an alcoholiiorm hydroxyl radical; 0OC.D. COO is the acid radical derived 'roooncoowamoi camoocnooon in which '1 is a radical derived by dehydroxylation of I a hydroxylated acylated diamide containing: (a) an acyl radical derived from a'polybasic carboxy acid having not more than 6 carbon atoms, and the acyl radical thereof linked to two amino nitrogen atoms; (12) a an acyl radical derived from adetergent-forming monocarboxy acid having at least 8 and'not more than 32 carbon atoms; and (c) an alcoholiform hy- ;drxy1 radical; OOC.D.COO is the acid radical derived from maleic acid by removal of the acidic I hydrogen atoms; and m represents a numeral varying from '7 to 12.

9. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of thefollowing formula type:

'roooncoowanloi mC2I-lZ4OOC.D.COO.T

I in which T is a radical derived by dehydroxylation of a hydroxylated acylated diamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more than 6 carbon atoms, and the acyl radical thereof linked to two amino nitrogen atoms; (12) an acyl radical derived from a detergent-forming monocarboxy acid having at least Sand not more than 32 carbon atoms; and (c) an alcoholiform hydroxyl radical; OOC.D.COO is the acidradical derived from succinicv acid by removal of the acidic hydrogen atoms; and m represents a numeral varying from 7 to 12. I

10. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a de mulsifying agent comprising a neutral, watersoluble chemical compound of the following formula type:

in which-T is a radical derived by dehydroxyla-' tion of a-hydroxylated acylated diamide containing: (a) an acyl radical derived from a polybasic carboxy acid having not more, than 6 carbonatoms, and the acyl radical thereof linked to two amino nitrogen atoms; (b) an acyl radical derived from a detergent-forming monocarboxy acid having at least 8 and not more than 32 carbon atoms; and (c) an alcoholiform hydroxyl radical; 00031000 is the acid radical A derived'from adipic acid by removal of the acidic hydrogen atoms; and m represents a numeral varying from. '7 to 12.

MELVIN DE GROOTE; BERNHARD KEISER. 

